4 replies to this topic

[OllyD]

Ok, so i've stripped my cylinder head in the past couple of days, as well as tackling what I thought was a broken fuel pump.My reasoning was the later i had a lot of fuel in my oil. But now that the head is off, my pistons are looking very cratered, with a definate ridge around the top of the bores. I know this means that the bores are worn, so could this be the cause of my problem with the petrol in the oil? If so, what are my options?

Reboring or new pistons, or anything involving taking the egine out is not even an option. Are there any ways to seal up the pistons if this could cause the cross-contamination?

[Dan]

No, if the engine is so worn that the cylinder seal is destroyed then it needs to come out and be overhauled with a rebore and new pistons or liners and the existing pistons with new rings. It could be that this has caused it because the same wear that has allowed so much blow by also stops the crankcase ventilation system working so the vapour doesn't get drawn out any more. It is more likely to be the fuel pump though.

[Big_Adam]

I know Mr Dan is very smart but it could just be carbon build up.

Pistons can look a bit hagged with lots of build up (got some in garage) but clean up fine. Althought if the car is running like a 1 legged dog thats been run over then the engines probably screwed.

edit

"Reboring or new pistons, or anything involving taking the egine out is not even an option. Are there any ways to seal up the pistons if this could cause the cross-contamination?"

One this point it is as Dan says, listen to the Dan, he is wise and knowledgeable beyond his years.

Edited by Big_Adam, 27 March 2007 - 08:33 PM.

[OllyD]

Hmm, tits. Guess i'll just have to put it all back together and hope for the best then. Would you recommend cleaning up the pistons then, or leaving them as they are? I seem to remember hearing something about the carbon build-up acting as a barrier when bores have become worn.

[Big_Adam]

To be honest the only way I cleaned the pistons I have is with a wire brush on a drill. Not really good to do in an engine.